How do you guys feel about THX certified speakers? Worth the extra dollar or not? I'm puting together a theater in my new home and have about $3k to spend on speakers. The entire house is going to be Klipsch and right now I am trying to decide between their R-7 line or their THX Ultra 2 setup. I'm getting all of these at dealer cost so it will in fact stay within my price range, but the Ultra 2 line runs about $500 more than the reference series... Is it worth doing?